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Title: Monitor has no color? Post by: Sonnyrayj on October 20, 2017, 12:28:29 pm As stated in subject, I have a Hitachi monitor that has no color. K7500 chassis. I have done a little reflowing and repaired a few traces. I have never worked on a monitor before so complete newbie here. I have looked at how to check the transistors but still am confused on the correct way to do that. After going and buying me some more glasses so I could actually see I looked over the board and components again and found the flyback has a small crack right above the focus knob. Would that tell me that the flyback is absolutely bad and would it cause a no color issue or should I be focusing more on the caps and transistors first for the color issue. When I say no color I mean it's not just missing a color or 2 it displays in black and white. Any help or advice would be greatly appreciated. I don't want to just be throwing money at it and my problem persist. Thanks
Title: Re: Monitor has no color Post by: Ramair1997 on October 21, 2017, 09:46:59 pm No color but a picture? Check the neck board, if the fly back is cracked you will hear a hiss or see arcing usually
Title: Re: Monitor has no color Post by: Sonnyrayj on October 22, 2017, 01:59:41 pm Thanks for the reply. I have found a small crack above the focus knob but never seen arcing or heard hissing. I am not certain on the correct way to check the transistors with a multi meter. There were some loose solder joints but I repaired them and retried. I did have a clearer picture but still only black and white.
Title: Re: Monitor has no color Post by: P-feif on October 22, 2017, 08:51:31 pm Any chance the red green and blue wires are tied together or somewhere in the chassis shorted together?
Title: Re: Monitor has no color Post by: Sonnyrayj on October 23, 2017, 07:49:15 am Will check. Thanks
Title: Re: Monitor has no color? Post by: Sonnyrayj on October 30, 2017, 08:24:57 pm Installed new c3782 transistors (that i didn't need and now understand how to check), glued pads back down and soldered everything up tight. Messed with color pots a little and was able to see all colors. Not exactly sure how to adjust but no matter how I adjust, it just floods the screen. There is no black back ground and then the color check bars showing up it just floods screen with color. Excited I did actually see something other than black and white but unsure of where to go from here. Any help would be greatly appreciated. Thanks
Title: Re: Monitor has no color? Post by: P-feif on November 01, 2017, 04:49:59 pm Pictures???
Title: Re: Monitor has no color? Post by: Sonnyrayj on November 01, 2017, 09:04:17 pm will try to get pics. tomorrow. Thanks
Title: Re: Monitor has no color? Post by: Sonnyrayj on November 02, 2017, 01:14:11 pm problem is now fixed thanks to Security0001 on the arcademuseum forum. It was the R811 resistor. thanks for your help though
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